Mercedes Actros MP4 1845 2013: MCM 900C02 Error - NOx Sensor Behind SCR Catalytic Converter Issue

Hi, can anyone help me, which means the error MCM 900C02 "nox sensor behind the SCR catalytic converter sporadic saved" error read with the delphi tester, unfortunately, it cannot be deleted on the board, the check engine light is blinking auto does not download adblue. Nox for the catalytic converter? List if it is the fault of something else

Added after 4 [minutes]:

Error photo

I would check the Nox sensor beam first ...

Hello, I understand that the topic is old, what was the cause of the fault?

@matys89 @speditionandros did you manage to embrace the topic?

The cause of the fault is an internal fault in the NOx sensor.

Procedure:

1) Check MCM and ACM modules for fault codes (if present) -> replace sensor B70 (NOx at exhaust aftertreatment inlet) -> clear fault memory.

After replacing the NOx sensor, no adaptation is necessary! Be careful when unscrewing it so as not to spoil the threads in the SCR catalytic converter.

2) (If there are no errors in the ACM module) -> update the ACM aftertreatment controller software at an authorised service centre.

Added after 10 [minutes]: .

>>19862449 >>19862449 .

The NOx sensor works according to the principle of an oxygen ionising duct.
Exhaust gas enters the sensor in the centre of which is a ceramic coating.
When NOX molecules are deposited on the ceramic coating, a signal / Nernst voltage is generated.
The nitrogen, carbon and hydrogen oxide molecules are oxidised by internal electrodes made of platinum. The process is repeated twice.
The signal voltage changes are then transmitted to the NOX sensor module (not to be confused with the ACM exhaust aftertreatment module!!!), which converts the analogue signals to digital and sends them to the ACM.

Potential causes of the fault :

- Malfunction of the NOX sensor module- faulty conversion of analogue to digital signals
- Internal failure of the sensor (ceramics / electrodes)

Regards,
Mercedes-Benz Truck technician